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When to Plant Leeks in San Jacinto County, TX

Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.

San Jacinto County, Texas is in USDA Zone 8b. The average last spring frost is February 18 and the first fall frost is December 1, giving you a growing season of approximately 286 days.

At an elevation of 6 feet, San Jacinto County receives approximately 71.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94ยฐF, providing good warmth for Leeks during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Leeks will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Leeks root diseases.

San Jacinto County, TX (Zone 8b) Year-round
286 days
Last Spring Frost February 18
286 growing days
First Fall Frost December 1

San Jacinto County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.3-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (119 days to spare)
Start indoors: Jan 6 Transplant: Feb 10 🍅 Harvest: May 12 – Jul 28
Recommended (50%) ✓ Fits season (118 days to spare)
Start indoors: Jan 14 Transplant: Feb 18 🍅 Harvest: May 20 – Aug 5
Safe Start (90%) ✓ Fits season (115 days to spare)
Start indoors: Feb 2 Transplant: Mar 9 🍅 Harvest: Jun 8 – Aug 24

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in San Jacinto County

How your county's soil matches Leeks's growing requirements.

Soil pH

Your soil pH (5.3โ€“6.7) overlaps with Leeks's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

Sandy soil in San Jacinto County warms quickly in spring but drains fast. Leeks will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Leeks.

How to Plant Leeks

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Leeks

Leeks needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Leeks Needs Rainfall You Supplement Action
Jan โ€” 1.7" 0" โ„๏ธ Dormant
Feb 3.5" 2.5" 1" ๐Ÿ’ง Light watering
Mar 3.5" 4.2" 0" โœ… Rainfall sufficient
Apr 3.5" 8.5" 0" โœ… Rainfall sufficient
May 3.5" 9.5" 0" โœ… Rainfall sufficient
Jun 3.5" 11.4" 0" โœ… Rainfall sufficient
Jul 3.5" 9.2" 0" โœ… Rainfall sufficient
Aug 3.5" 8" 0" โœ… Rainfall sufficient
Sep 3.5" 6.7" 0" โœ… Rainfall sufficient
Oct 3.5" 5.2" 0" โœ… Rainfall sufficient
Nov 3.5" 2.6" 0.9" ๐Ÿ’ง Light watering
Dec 3.5" 1.9" 1.6" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Febโ€“Dec in San Jacinto County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Leeks Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Leeks needs ~2,460 GDD — county provides 5,883 GDD Excellent fit

Leeks Planting Timeline โ€” San Jacinto County, TX

Leeks Planting Calendar

Activity When Date Range
Start Indoors January 14 Jan 14 โ€“ Jan 28
Transplant Outdoors February 18 Feb 18 โ€“ Mar 4
Direct Sow February 4 Feb 4 โ€“ Feb 25
Harvest May 20 May 20 โ€“ Aug 5
Fall Sowing September 22 Sep 22 โ€“ Oct 6

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Transplant Outdoors Direct Sow
March Transplant Outdoors
April โ€”
May Harvest
June Harvest
July Harvest
August Harvest
September Fall Sowing
October Fall Sowing
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.8"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“150 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

286 days in San Jacinto County

Growing Tips for Leeks in San Jacinto County

Direct sow Leeks outdoors after February 18 in San Jacinto County when soil has warmed and frost danger has passed.

Sandy soil in San Jacinto County dries quickly โ€” mulch Leeks with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Leeks in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Leeks in San Jacinto County, TX?

San Jacinto County is in Zone 8b with an average last frost of February 18. Plan your Leeks planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is San Jacinto County, TX?

San Jacinto County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is February 18 and first fall frost is December 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help San Jacinto County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for San Jacinto County, TX. Local conditions may vary. Last updated: April 2026.